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Blueprint for fault-tolerant quantum computation with topological qubit arrays

David Aasen, Morteza Aghaee, Zulfi Alam, Mariusz Andrzejczuk, Andrey Antipov, Mikhail Astafev, Lukas Avilovas, Amin Barzegar, Bela Bauer et al.

Jonathan Becker, Juan M. Bello-Rivas, Umesh Bhaskar, Alex Bocharov, Srini Boddapati, David Bohn, Jouri Bommer, Parsa Bonderson, Jan Borovsky, Leo Bourdet, Samuel Boutin, Tom Brown, Gary Campbell, Lucas Casparis, Srivatsa Chakravarthi, Rui Chao, Benjamin J. Chapman, Sohail Chatoor, Anna Wulff Christensen, Patrick Codd, William Cole, Paul Cooper, Fabiano Corsetti, Ajuan Cui, Wim van Dam, Tareq El Dandachi, Sahar Daraeizadeh, Adrian Dumitrascu, Andreas Ekefjärd, Saeed Fallahi, Luca Galletti, Geoff Gardner, Raghu Gatta, Haris Gavranovic, Michael Goulding, Deshan Govender, Flavio Griggio, Ruben Grigoryan, Sebastian Grijalva, Sergei Gronin, Jan Gukelberger, Jeongwan Haah, Marzie Hamdast, Esben Bork Hansen, Matthew Hastings, Sebastian Heedt, Samantha Ho, Justin Hogaboam, Laurens Holgaard, Kevin Van Hoogdalem, Jinnapat Indrapiromkul, Henrik Ingerslev, Lovro Ivancevic, Sarah Jablonski, Thomas Jensen, Jaspreet Jhoja, Jeffrey Jones, Kostya Kalashnikov, Ray Kallaher, Rachpon Kalra, Farhad Karimi, Torsten Karzig, Seth Kimes, Vadym Kliuchnikov, Maren Elisabeth Kloster, Christina Knapp, Derek Knee, Jonne Koski, Pasi Kostamo, Jamie Kuesel, Brad Lackey, Tom Laeven, Jeffrey Lai, Gijs de Lange, Thorvald Larsen, Jason Lee, Kyunghoon Lee, Grant Leum, Kongyi Li, Tyler Lindemann, Marijn Lucas, Roman Lutchyn, Morten Hannibal Madsen, Nash Madulid, Michael Manfra, Signe Brynold Markussen, Esteban Martinez, Marco Mattila, Jake Mattinson, Robert McNeil, Antonio Rodolph Mei, Ryan V. Mishmash, Gopakumar Mohandas, Christian Mollgaard, Michiel de Moor, Trevor Morgan, George Moussa, Anirudh Narla, Chetan Nayak*, Jens Hedegaard Nielsen, William Hvidtfelt Padkær Nielsen, Frédéric Nolet, Mike Nystrom, Eoin O’Farrell, Keita Otani, Adam Paetznick, Camille Papon, Andres Paz, Karl Petersson, Luca Petit, Dima Pikulin, Diego Olivier Fernandez Pons, Sam Quinn, Mohana Rajpalke, Alejandro Alcaraz Ramirez, Katrine Rasmussen, David Razmadze, Ben Reichardt, Yuan Ren, Ken Reneris, Roy Riccomini, Ivan Sadovskyy, Lauri Sainiemi, Juan Carlos Estrada Saldaña, Irene Sanlorenzo, Simon Schaal, Emma Schmidgall, Cristina Sfiligoj, Marcus P. da Silva, Shilpi Singh, Sarat Sinha, Mathias Soeken, Patrick Sohr, Tomas Stankevic, Lieuwe Stek, Patrick Strøm-Hansen, Eric Stuppard, Aarthi Sundaram, Henri Suominen, Judith Suter, Satoshi Suzuki, Krysta Svore, Sam Teicher, Nivetha Thiyagarajah, Raj Tholapi, Mason Thomas, Dennis Tom, Emily Toomey, Josh Tracy, Matthias Troyer, Michelle Turley, Matthew D. Turner, Shivendra Upadhyay, Ivan Urban, Alexander Vaschillo, Dmitrii Viazmitinov, Dominik Vogel, Zhenghan Wang, John Watson, Alex Webster, Joseph Weston, Timothy Williamson, Georg W. Winkler, David J. van Woerkom, Brian Paquelet Wütz, Chung Kai Yang, Richard Yu, Emrah Yucelen, Jesús Herranz Zamorano, Roland Zeisel, Guoji Zheng, Justin Zilke, and Andrew Zimmerman

  • 1 Microsoft Way, Redmond, Washington 98052, USA

  • *Contact author: cnayak@microsoft.com
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Phys. Rev. Research 7, 041002 – Published 24 December, 2025

DOI: https://doi.org/10.1103/qx36-4rv1

Abstract

We describe a concrete device roadmap toward a fault-tolerant quantum computing architecture based on noise-resilient, topologically protected Majorana-based qubits. Our roadmap encompasses four generations of devices: a single-qubit device that enables a measurement-based qubit benchmarking protocol; a two-qubit device that uses measurement-based braiding to perform single-qubit Clifford operations; an eight-qubit device that can be used to show an improvement of a two-qubit operation when performed on logical qubits rather than directly on physical qubits; and a topological qubit array supporting lattice surgery demonstrations on two logical qubits. Devices that enable this path require a superconductor-semiconductor heterostructure that supports a topological phase, quantum dots and coupling between those quantum dots that can create the appropriate loops for interferometric measurements, and a microwave readout system that can perform fast, low-error single-shot measurements. We describe the key design components of these qubit devices, along with the associated protocols for demonstrations of single-qubit benchmarking, Clifford gate execution, quantum error detection, and quantum error correction, which differ greatly from those in more conventional qubits. Finally, we comment on implications and advantages of this architecture for utility-scale quantum computation.

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Phys. Rev. Research 7, 041002– Published 24 December, 2025
  • Received 31 December 2024
  • Revised 18 July 2025
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